If looks could kill, Kim and Kourtney Kardashian might both be goners.

The sisters, who aren't unused to finding themselves in heated arguments, made particularly powerful waves this week when a preview of the forthcoming Keeping Up With the Kardashians season premiered, and found the sisters in a fight that's kind of unprecedented.

The upshot is this: Kim arranged a photo shoot and Kourtney stipulated that she had to leave by a particular time. Kim, for some reason, took this as recalcitrance, and decided to take Kourtney down a peg by insulting her business acumen and concluding her tirade with this totally savage takedown:

"You're the least interesting to look at."

Yikes, yikes, yikes.

Later, Kourtney tried resolving the tiff over the phone with Kim, but Kim wasn't having it, and doubled down on her mud-slinging.

It was all pretty tough to watch, but is this really anything new — have you considered that maybe the sisters have been harboring resentment for each other since KUWTK premiered?

In light of the fighting that's sure to come from the next season, we've arranged a photo gallery of Kim and Kourtney Kardashian looking like they'd like to kill each other while stuck in the other's company. Take a look, and to see everything play out, tune in to the Keeping Up premiere on August 6 on E!.

Kim + Kourtney Look Like They Want To Kill Each Other